Packing devices comprising fixed and movable elements for rotary engines



May 25, 1965 L. PERAS 3,185,386

PACKING DEVICE-S COMPRISING FIXED AND MOVABLE ELEMENTS FOR ROTARY ENGINES 2 Sheets-Sheet 1 Filed Aug. 24, 1961 Invent-n- PERAS 3,185,386 ICES COMPRISING FIXED AND MOVABLE ELEMENTS FOR ROTARY ENGINES May 25, 1965 PACKING DEV 2 Sheets-Sheet 2 Filed Aug. 24, 1961 United States Patent 3,185,386 PACKING DEVICES COMPRISING FIXED AND MOVABLE ELEMENTS FOR ROTARY ENGINES Lucien Paras, Billancourt, France, assignor to Regie Nationale des Usines Renault, Billancourt, France Filed Aug. 24, 1961, Ser. No. 133,632 Claims priority, application France, Sept. 20, 1960, 839,013, Patent 1,277,311 3 Claims. (Cl. 230-145) This invention relates to .packing devices for rotary engines of the lobar type comprising an eccentric rotor having 2N lobes and a stator having 2N +1 lobes, wherein the rotor contour is an epicycloid and the stator contour an envelope curve having its contour conjugated with the rotor epicycloid.

The number of contact points between the two contours equals the number of lobes of the envelope curve and it is this number (2N+l) that determines the number of working chambers in which the cycle of operation of the engine takes place. Associated with these 2N+1 working chambers are 2N +1 combustion chambers in which the inlet and exhaust valves as well as the spark plug are mounted.

This invention relates more particularly but not exclusively to engines of the type defined hereinabove, wherein the combustion chambers are disposed peripherally in relation to each working chamber; therefore, these combustion chambers are formed in the stator.

In an engine of this type the present invention provides packing means for sealing the joints against gas and oil leakages, in the form of fixed partitioning means disposed in the stator and of rotary partitioning means disposed in the rotor.

These fixed partitioning means consist of elements described in the patent application Serial No. 133,631 filed on the same date by the same applicant and entitled Packing for rotary engines, that is, strips or sections fitted in grooves or like recesses formed in the stator at the junctions of adjacent lobes, these strips or sections resiliently engaging the epicyclic contour of the rotor along one generatrix, the movable partitioning means of the present invention consisting on the one hand of lateral strips following a substantially epicyclic path, which are fitted in recesses or grooves formed in the lateral faces of the rotor so as to fit closely the epicyclic contour of the rotor, and on the other hand of circular strips disposed within said epicyclic strips and adapted to seal the engine more particularly against oil leakages through the bearing.

With the foregoing and other objects in view, the invention resides in the novel arrangement and combination of par-ts and in the details of construction hereafter described and claimed, it being understood that changes in the precise embodiment of the invention herein disclosed may be made within the scope of what is claimed without departing from the spirit of the invention.

Other objects and advantages will become apparent from the following description taken in conjunction with the accompanying drawing in which:

FIGURE 1 is a complete view showing the rotor and stator assembly, the upper or front flange or cover being removed to show the fixed and movable partitioning means constituting the subject-matter of this invention;

FIGURE 2 is a detail section showing the fixed radial partitioning means mounted in the stator and complementary strips constantly bearing on the epicyclic strip or forming a narrow gap with this section;

FIGURES 2a and 2b are sections taken along the lines a-a and bb of FIGURE 2 respectively;

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FIGURE 3 is a modified embodiment of the structure shown in FIG. 2;

FIGURES 3a and 3b are sections taken across the lines a-a and bb of FIG. 3 respectively;

FIGURES 4 and 4a are diiferent embodiments of the epicyclic strip, and

FIGURE 5 is a detail section showing an alternate embodiment of the lateral sealing member.

In the form of embodiment illustrated in FIG. 1, the rotary engine comprises the rotor 1 disposed in the stator 2 in which working chambers 3 as well as combustion chambers 4 are formed; these chambers receive the inlet and exhaust valves 5, 6 as well as the spark plugs 7.

To seal this engine against gas and oil leakages the fixed radial strips 8 mounted on the stator and bearing on the rotor in order to seal the Working chambers from one another are complemented by an epicyclic movable strip 9 and a circular movable strip 10 both mounted on the rotor.

FIGURES 2, 2a and 2b illustrate in section fixed strips according to a diametral plane of the engine, according to a specific embodiment of the invention, each fixed strip 8 is fitted in a groove 12 formed in the stator, a corrugated spring blade 11 being fitted in the bottom of this groove for resiliently pressing the strip against the peripheral contour of the rotor. To seal the ends of this strip a complementary strip 15 housed in a blind hole 14 formed in the flange or cover 13 of the stator 2 is resiliently urged by a spring 18 against the same relevant end of strip 8.

The end strip 15 bears at the same time against the epicyclic strip 9 and these two members are adapted to slide on each other; to this end, each strip 15 may be formed at its outer portion with a rounded contour 19 or any other suitable contour and the strip 8 may also have a rounded contour 20 if desired.

More particularly, the member 15 fits in a slot 16 formed in a member 17 force fitted in the recess 14. In an alternate embodiment illustrated in FIGURES 3, 3a and 3b, the complementary strip 15' is disposed directly in a recess 21, a corrugated spring blade 22 causing the elastic relative engagement between the components.

Finally, the epicyclic strip 9 may advantageously consist of a set of resilient leaf springs 23 of moderate thickness which are urged against the flange or cover 13 by a corrugated spring blade 24 (FIG. 4).

If desired, another corrugated spring blade 25 may be added centrally of these leaf springs, this blade corresponding substantially in shape to these springs 23 and serving the purpose of producing the sealing contact with the lateral faces of the epicyclic groove (FIG. 4a).

FIGURE 5 illustrates in section an alternate embodiment of the lateral sealing device wherein the bearing member 15 is replaced by a circular piston 26 guided in a recess 27 formed in the flange or cover 13. This piston is disposed astride so as to bear both on the strip 8 and on the epicyclic strip 9, and is subjected to the resilient force of a helical spring 28.

Of course, other modifications and alterations could be brought to the packing means described and illustrated herein, without departing from the spirit and scope of the invention.

I claim:

1. Packing device for a rotary engine of the lobar type comprising an eccentric rotor of substantially epicyclic contour having 2N lobes and a stator providing a chamber therein having 2nr+1 lobes and having end covers for said chamber, wherein combustion chambers are disposed around the outer periphery of the rotor in said stator, the rotor being mounted for rolling intermeshing relation of the lobes thereof with the stator lobes,

said rotor lobes and stator lobes thereby forming expansible and contractible fluid working chambers therebetween, said packing device comprising fixed radial sealing strips disposed in the stator along the line of junction between adjacent working chambers, movable sealing strips carried by said rotor and consisting on the one hand of lateral sealing strips of substantially epicyclic contour located at a relatively short distance from the epicyclic surface of said rotor, and on the other hand of circular sealing strips disposed inside said epicyclic 10 sealing strips also on the lateral faces of the rotor, and complementary sealing strips in each stator cover end- Wise of said radial sealing strips, resiliently engaging both said radial sealing strips and the epicyclic sealing strips in order to provide the necessary lateral fluid-tightness.

2. Packing device according to claim 1, characterized in that said sealing strips consist of strips urged by spring means to their sealing position.

4 3. Packing device according to claim 2, characterized in that said epicyclic strips consist of stackings of leafsprings.

References Cited by the Examiner UNITED STATES PATENTS 748,348 12/03 Cooley. 1,310,157 7/19 De Campo 9156 3,033,180 5/62 Bentele l238 FOREIGN PATENTS 1,057,613 5/59 Germany.

24,559 1908 Great Britain.

15 KARL J. ALBRECHT, Primary Examiner.

WILLIAM FELDMAN, JOSEPH H. BRANSON, JR.,

Examiners. 

1. PACKING DEVICE FOR A ROTARY ENGINE OF THE LOBAR TYPE COMPRISING AN ECCENTRIC ROTOR OF SUBSTANTIALLY EPICYCLIC CONTOUR HAVING 2N LOBES AND A STATOR PROVIDING A CHAMBER THEREIN HAVING 2N+1 LOBES AND HAVING END COVERS FOR SAID CHAMBER, WHEREIN COMBUSTION CHAMBERS ARE DISPOSED AROUND THE OUTER PERIPHERY OF THE ROTOR IN SAID STATOR, THE ROTOR BEING MOUNTED FOR ROLLING INTERMESHING RELATION OF THE LOBES THEREOF WITH THE STATOR LOBES, SAID ROTOR LOBES AND STATOR LOBES THEREBY FORMING EXPANSIBLE AND CONTRACTIBLE FLUID WORKING CHAMBERS THEREBETWEEN, SAID PACKING DEVICE COMPRISING FIXED RADIAL SEALING STRIPS DISPOSED IN THE STATOR ALONG THE LINE OF JUNCTION BETWEEN ADJACENT WORKING CHAMBERS, MOVABLE SEALING STRIPS CARRIED BY SAID ROTOR AND CONSISTING ON THE ONE HAND OF LATERAL SEALING STRIPS OF SUBSTANTIALLY EPICYCLIC CONTOUR LOCATED AT A RELATIVELY SHORT DISTANCE FROM THE EPICYCLIC SURFACE OF SAID ROTOR, AND ON THE OTHER HAND OF CIRCULAR SEALING STIPS DIPOSED INSIDE SAID EPICYCLIC SEALING STRIPS ALSO ON THE LATERAL FACES OF THE ROTOR, AND COMPLEMENTARY SEALING STRIPS, RESILIENTLY ENGAGING BOTH WISE OF SAID RADIAL SEALING STRIPS, RESILIENTLY ENGAGING BOTH SAID RADIAL SEALING STRIPS AND THE EPICYCLIC SEALING STRIPS IN ORDER TO PROVIDE THE NECESSARY LATERAL FLUID-TIGHTNESS. 